摘要
在微波-超声波协同作用下,采用尿素为沉淀剂,与一定浓度的DyCl_(3)溶液充分反应之后,得到Dy_(2)O_(3)前驱体(Dy(OH)CO_(3)·H_(2)O),煅烧后得到纳米球形Dy_(2)O_(3)。探究了Dy^(3+)浓度、尿素浓度以及超声波功率对Dy_(2)O_(3)前驱体微观形貌的影响。采用扫描电子显微镜、同步热分析仪、X射线衍射仪、傅里叶红外光谱仪对Dy2O3前驱体煅烧前后的微观形貌、微观结构进行了表征,对煅烧分解机理进行了分析。结果表明:当控制Dy^(3+)浓度0.045 mol/L,尿素浓度2.5 mol/L,微波功率500 W,超声功率800 W,超声波模式1∶2,反应时间1 h,反应温度90℃时,可以得到粒径均一、表面光滑、分散程度好且粒径约为220 nm的Dy(OH)CO_(3)·H_(2)O。在800℃的煅烧温度下该前驱体可完全分解,最终得到粒径约为200 nm的纳米球形Dy_(2)O_(3)。
Under the synergistic action of microwave-ultrasonic, Dy_(2)O_(3) precursor(Dy(OH)CO_(3)·H_(2)O) was prepared by the reaction of a certain concentration of DyCl_(3) solution with urea as precipitant, and then the nano spherical Dy2O3 was obtained by calcination.The effects of Dy^(3+) concentration, urea concentration and ultrasonic power on the morphology of Dy_(2)O_(3) precursor were explored.The morphology and microstructure of Dy_(2)O_(3) precursor before and after calcination were characterized, and the calcination decomposition mechanism was analyzed by scanning electron microscope, synchronous thermal analyzer, X-ray diffractometer, and Fourier infrared spectrometer.The results show that Dy(OH)CO_(3)·H_(2)O with uniform particle size, smooth surface, good dispersion and particle size of about 220 nm can be obtained under the conditions of Dy^(3+) concentration of 0.045 mol/L,urea concentration of 2.5 mol/L,microwave power of 500 W,ultrasonic power of 800 W,ultrasonic mode of 1∶2,reaction time of 1 h and reaction temperature of 90 ℃.The precursor can be completely decomposed at the calcination temperature of 800 ℃,and nano spherical Dy_(2)O_(3) with particle size of about 200 nm can be obtained.
作者
邓庚凤
李志午
周小明
DENG Geng-feng;LI Zhi-wu;ZHOU Xiao-ming(Department of Materials Metallurgy Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2021年第2期29-35,共7页
Rare Metals and Cemented Carbides
基金
国家自然科学基金(51564022)。
